It contains a total of 118 poems, including unpublished works produced in solo by YOSHII LOVINSON and Kazuya Yoshii. The culmination of 20 years.

YOSHII LOVINSON and Kazuya Yoshii released the lyrics of the song "Solo" from 2003 to 2023. This is a permanent preservation version of a hard cover that contains a total of 118 poems including unpublished works, including handwritten lyrics drafts spelled in notes, background and feelings at the time of production, etc.

◾️ Excerpt from the person's comment (in the book)
「BEAUTIFUL」
I wrote while walking around Komazawa Park in the neighborhood of an apartment where I lived alone at that time. This "grassland" was the same place as the scenery where the young grass that appeared in the later "Mirai no Uta" grew.

「STRONGER」
When I went abroad, there were children singing hymns in a large church, and I filmed a video with too much beauty. In the second half of the song, the sound at that time was sampled. Wonderful and the key matched.